Another 14 people are missing after the attack on the town of Pava in Choco province by the Revolutionary Armed Forces of Colombia, which took place some time over the past few days, police said, without providing more details.
Communications with towns cut off by thick rain forest are often slow, and sometimes only possible by river.
There was no immediate explanation for the attack by the rebel army known by its Spanish initials FARC.
But the area is a key smuggling route for exporting cocaine and importing weapons by illegal armed groups of both the right and left that are fighting in the country's 41-year-old guerrilla war, which claims thousands of lives a year.
It also came as outlawed far-right paramilitaries who control much of the area have offered to discuss a peace deal with the government. The paramilitaries have their origins in militias set up by cocaine smugglers and cattle ranchers to defend their property against the FARC.
Many Colombians fear the FARC could seek to move into areas where paramilitaries disarm.
- Reuters - Thomson Reuters Foundation
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